MTV Stations (TCM)

Optical Transition Radiators are used to measure beam sizes and compute the beam emittance and the twiss parameters.

Layout

In CTF3, profile measurements using OTR are performed using optical lines that consist of two achromatic lenses that guide the emitted OTR to a standard CCD camera placed at floor level inside a shielding box. With the first achromat installed at a distance of only ~50 cm, this layout guarantees capturing most of the emitted light while maintaining a good spatial resolution. Today, all installations at CTF3 aiming at transverse profile measurements using OTR follow the design shown to the left.

In total, at least four mirrors are installed to guide the OTR light towards the camera. The distances between the different elements slightly vary from one system to another due to spatial constraints. Different radiators including scintillating screens, Aluminum, Carbon and SiC have been used and other materials are under consideration.